django class with an array of "parent" foreignkeys issue
- by user298032
Let's say I have a class called Fruit with child classes of the different kinds of Fruit with their own specific attributes, and I want to collect them in a FruitBasket:
class Fruit(models.Model):
type = models.CharField(max_length=120,default='banana',choices=FRUIT_TYPES)
...
class Banana(Fruit):
"""banana (fruit type)"""
length = models.IntegerField(blank=True, null=True)
...
class Orange(Fruit):
"""orange (fruit type)"""
diameter = models.IntegerField(blank=True, null=True)
...
class FruitBasket(models.Model):
fruits = models.ManyToManyField(Fruit)
...
The problem I seem to be having is when I retrieve and inspect the Fruits in a FruitBasket, I only retrieve the Fruit base class and can't get at the Fruit child class attributes.
I think I understand what is happening--when the array is retrieved from the database, the only fields that are retrieved are the Fruit base class fields. But is there some way to get the child class attributes as well without multiple expensive database transactions? (For example, I could get the array, then retrieve the child Fruit classes by the id of each array element).
thanks in advance, Chuck
